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Stroke and myocardial infarction are initiated by rupturing vulnerable atherosclerotic plaques. With noninvasive ultrasound elastography, these plaques might be detected in carotid arteries. However, since the ultrasound beam is generally not aligned with the radial direction in which the artery pulsates, radial and circumferential strains need to be derived from axial and lateral data. Conventional techniques to perform this conversion have the disadvantage that lateral strain is required. Since the lateral strain has relatively poor accuracy, the quality of the radial and circumferential strains is reduced. In this study, the radial and circumferential strain estimates are improved by combining axial strain data acquired at multiple insonification angles. Adaptive techniques to correct for grating lobe interference and other artifacts that occur when performing beam steering at large angles are introduced. Acquisitions at multiple angles are performed with a beam steered linear array. For each beam steered angle, there are two spatially restricted regions of the circular vessel cross section where the axial strain is closely aligned with the radial strain and two spatially restricted regions (different from the radial strain regions) where the axial strain is closely aligned with the circumferential strain. These segments with high quality strain estimates are compounded to form radial or circumferential strain images. Compound radial and circumferential strain images were constructed for a homogeneous vessel phantom with a concentric lumen subjected to different intraluminal pressures. Comparison of the elastographic signal-to-noise ratio (SNR(e)) and contrast-to-noise ratio (CNR(e)) revealed that compounding increases the image quality considerably compared to images from 0 degrees information only. SNR(e) and CNR(e) increase up to 2.7 and 6.6 dB, respectively. The highest image quality was achieved by projecting axial data, completed with a small segment determined by either principal component analysis or by application of a rotation matrix.

Ultrasound strain imaging is used to measure local tissue deformations. Usually, only strains along the ultrasound beam are estimated, because those estimates are most precise, due to the availability of phase information. For estimating strain in other directions we propose to steer the ultrasound beam at an angle, which allows estimating different projections of the 2D strain tensor, while phase information remains available. This study investigates beam steering at maximally three different angles to determine the full 2D strain tensor. The method was tested on simulated and experimental data of an inclusion phantom and a vessel phantom. The combination of data from a non-steered acquisition and acquisitions at a large positive and an equally large but negative steering angle enabled the most precise estimation of the strain components. The method outperforms conventional methods that do not use beam steering.

Background: Adalimumab is the only approved compound for the treatment of adult patients with moderate-to-severe hidradenitis suppurativa (HS) who did not respond to a systemic classical treatment. Despite its significant short- and long-term efficacy, a percentage of patients do not respond sufficiently. Moreover, some primary responders experience a response loss with time. Objective: To analyse the effectiveness of adalimumab dose intensification in HS patients. Methods: A case series of adalimumab 80 mg/week subcutaneously (s.c.) compassionate use in patients with HS, who did not respond sufficiently or in primary responders with progressive response loss to the registered adalimumab dose of 40 mg/week s.c. Patients were collected and evaluated retrospectively. Patients’ data were extracted from medical records. Results: The 14 patients collected were Caucasian with HS of Hurley stage II–III and moderate or severe International HS Severity Score System (IHS4) stage. Adalimumab dose intensification significantly improved IHS4 score, Pain Index, HS-Physician Global Assessment, pain, and Cardiff Dermatology Life Quality Index. Two young female patients with HS and Crohn’s disease developed psoriatic lesions during the treatment with adalimumab 80 mg/week s.c. Conclusion: An enhanced level of effectiveness was assessed in the majority of the HS patients treated with adalimumab dose intensification (80 mg/week s.c.). Larger studies are required to evaluate this observation.

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